There has been a recent increase in research and development of User Authentication (UA) models with various modalities such as voice [1]}, [2]}, face [3]}, fingerprint [4]}, or iris [5]}. Many commercial smart devices such as mobile phones, AI speakers and automotive infotainment systems have adopted machine learning-based UA features for unlocking the system or providing a user-specific service, e.g., music recommendation, schedule notification, or other configuration adjustments.
